Centile charts for cranial sutures in children younger than 1 year based on ultrasound measurements.

BACKGROUND: Cranial US allows for the evaluation of premature closure (synostosis) or abnormal widening of the cranial sutures. An understanding of the normal anatomy is required to help define the presence or absence of abnormality.

OBJECTIVE: To provide reference for normal ultrasound measurements of cranial sutures during the child's first year.

MATERIALS AND METHODS: We included children ages 0 to 12 months who were referred to the hospital during 2011-2013 for radiographic evaluation of cranial sutures. Cranial US study was focused on evaluating the sagittal, coronal, lambdoid and metopic sutures. We measured the hypoechoic gap between the bones (patent suture). Two readers performed the measurements, blinded to clinical indications and previous reports. Estimates of the 10th , 25th , 50th , 75th and 90th percentiles were achieved for ages 1-12 months.

RESULTS: Of 129 children whose families consented to cranial US, 11 were excluded because of craniosynostosis and 3 for suboptimal quality of cranial US images. In 115 patients measurements of normal cranial sutures were obtained (75 boys [65%], ages 0.26-11.27 months). For each suture, the suture size decreased significantly with age (P<0.001). Only the metopic suture was noted to close completely toward the end of the first year of age. There were no statistically significant differences in age-related suture size by gender.

CONCLUSION: The current patient series represents a reference of percentiles of normal ultrasound measurements of cranial sutures during the first year of age.